Air cleaner for carburetors



June 21, 1949. SMITH ETAL 2,474,017

AIR CLEANER FOR CARBURETORS Filed March 21, 1946 al j F219. 2 9 I 4 1 j, 4/ I I b b 04 a Patented June 21, 1949 STATES OFFICE AIR CLEANER FOR CARBURETORS Ellis Smith and Norris CrabtreeyBradford, Sydney Naylor, Wibsey, Bradford; and Harold James.

Maw, Guiseley," England Application March 21, 194.6; Serial No. 656,066 In Great Britain J'uly 26;1945' 5 Claims;

Our-inventiomin or relatingtocarburettersfermotor vehicles has particular reference tovide; behind-: the' radiator; a conical or funnel-- mouthed tubular-member, the larger end of Wh ic'h f-will beiopposed to'the hot air stream induoed thrOugh 'the-radiatQr-by the cooling fan; whilst-its-smaller end fits in or over or is suitably connected' to the primary air inlet to the carburetter.

Thus; instead of the carburetter depending forits supply upon the vacuum in the in duction pipe. it'will receive a supply of warm air under a-=pressure-which will vary with the speed of the engine.

Incorporated-inthe device is a filter of such construction that a portionof the air stream is utilized to discharge-anyparticlesof, dirt or gritt which may be carried into the filter.

Irv-the accompanying drawing; Fi'gi l is a sectional elevation of one practical embodimentofthe. invention, suitable. for use. when I the: improved primaryair supply device. canlbeflocatedion the same side 0f the engine ofi'sa motor. vehicle as the carburetter;

Figs 2.; shows a formof construction which maybe employed where the supply device for the primary't'airicannot, to=-the: best advantage, be locatedionutheisame -side of the engine as the.

carburetter;

Referring to the drawing, a. represents 'a tubular member, preferably though not necessarilyv of fcircul'ar cross-section, having a frusto-conical orr'funnel-shaped inlet end a and. .its opposite en'd lia. closed; Ata suitable point in the length Of- -th'eimember a -ther 'isprovided an outlet 0. adaptedta. be: fitted over, orappropriately con nectedrto; theprimary-air inlet of the carburetter.

of: as motor vehicle:

Within. the. member a: there is provided an inneror 'filter member' b of gauze or equivalent perforated material-and of such smaller diameter theiouterrmemher: that an annular space:

oft suitable thickness. or area-is provided between the? two' m'embers.

Theiendiof 'the perforatedfilter member 17 21 with a fru-sto-conical inlet "member 0 which closes the end of the annulus between the members-a and b'.

The end of the perforated filter member b- 1 oppositeto the-inlet isclosed as at b with the exception of a" relatively small-opening b near itsbottom. The filter member b is, as shown, preferably made slightlyirusto-conical in form,

with'the smaller end adjacent the inlet. The result of :such auconstructi'on is that the bottom ofz'theinteriorcsurface:ofsthe said filter member slopes idownwardlyztowardsmhe opening 13 Any particlespf dirt -or grit whichmay be drawn into' theifilter. will thus tendtto gravitate towards and: be expelledthrough'the'opening 22 A nozzle,

b -with::a restrictedroutlet orifice b may be provided.toverutheeopeningb The device is suitablysupportednin rear of the radiator of a I vehicle" and preferably on that side oft-the engine from which the usual cooling fan is rotating-downwardly; this location being found to give the best results. The-distance of;

the-inletend a'from-therear-iace of the radiator willhnecessarily: be 'govern'ed to a certain extent bycircumstances, .thatis -to say by-the construction-and arrangement of the engine of the vehicle concerned: Ifconvenient; it may be so located that the-outlet a3 can-be applied directly into or. .overthe primary air inlet tothe carburetten Ifthis is nOticOnVenient, a'suitablepipe connection' may; be made between'the supply device and vthe carburetter.

Air entering..,the.inlet a. is concentrated and forced .to. flow with increased velocity' through th'erfilterab to the-.air-intake of the carburetter, andthe greater the quantity; of demanded by the:.:engine-,.that is:to,.say the greater the speed ofethefvehicle thegreater will .bethe volume of airqsupplied-i In cases zwhereit is-znecessary or desirable to haveastheainlet to: the improved primary air supplyg'devicecon the .opposite: side of the engine to the carburetter, as constructional arrangement such astthat shown. in Fig. 2 may be adopted.

* In. thiszcasethe-filter member-b; instead of being in line with the inlet end :of -thedeviceextends atrightranglesto lit-(or at any such other angle asrmaysbe convenient).

As before; a'frusto-conical :member' 0. connects theuiniet withthe-filter .member I) The outlet a .for;thezfilteredzaimis, in this instance, shown as being-at. the end or .thedevice instead of being locatedaata point .inxthe length of the member.

(1153,83 inzFiggil... The :connection between .the outletia anditheeair intake to:-the-;carburetter will,v

of course, depend upon the location of the latter on the engine. For some vehicles, it may be preferable to have the air outlet disposed at some point along the length of the member a as in Fig. 1 and the outlet for grit and dirt in an otherwise closed end of the filter member b, also as in Fig. 1.

Whilst we have shown the filter as being located in and forming part of the air collecting and concentrating member, it will be apparent that it need not necessarily be so located but may be included in the connection to the air inlet of the carburetter. For many reasons, however, the constructions shown are to be preferred.

Whilst being extremely simple and easy to apply, the air-collecting, concentrating, filtering and delivering device according to the invention has been found to improve markedly the fuelconsumption figures of a variety of different makes of motor vehicles.

Have thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A primary air admission device for a motor carburetor comprising in combination a closed casing; an inlet opening in said casing for the air to be admitted to said motor carburetor; a first outlet openin in said casing adapted to be connected to said motor carburetor; a filter member within said casing through which the air is forced to pass on its Way from said inlet opening to said first outlet opening; a second outlet opening in said casing leading into the space surrounding said casing; and an unobstructed outlet opening in said filter member through which a portion of the air passing through said casing might reach without obstruction said second outlet opening in said casing, carrying any grit or dirt contained in the air admitted through said inlet opening directly into the space surrounding said casing.

2. A primary air admission device for a motor carburetor comprising in combination a tubular casing; an inlet opening at one end of said tubular casing for the fresh air to be admitted to said motor carburetor; a first outlet opening in said tubular casing adapted to be connected to said motor carburetor; a tubular filter member Within said tubular casing through which the fresh air is forced to pass on its way from said inlet opening to said first outlet opening; a second outlet opening in said tubular casing leading into the space surrounding said tubular casing; and an unobstructed outlet opening in said tubular filter member connected to said second outlet openin in said tubular casing through which a portion of the air passing through said tubular casing and said tubular filter within the same might be expelled into the space surrounding said tubular casing without the necessity of passing through the filter wall of said tubular filter member within the same, carrying any grit or dirt contained in the air admitted through said inlet opening directly into the space surrounding said casing.

3. A primary air admission device for a motor carburetor comprising in combination a tubular casing having a substantially cylindrical wall; an inlet opening at one end of said tubular casing for the fresh air to be admitted to said motor carburetor; a first outlet opening in said cylindrical wall of said tubular casing adapted to be connected to said motor carburetor; a tubular filter member arranged within said tubular cas- Cal ing and having a substantially cylindrical filter wall through which the fresh air is forced to pass on its way from said inlet opening to said first outlet opening; a second outlet opening at the other end of said tubular casing leading into the space surrounding said tubular casing; and an unobstructed outlet opening at the corresponding end of the tubular filter member connected with said second outlet opening at the other end of said tubular casing through which a portion of the air passing through said tubular casing and said tubular filter within the same might be expelled into the space surrounding said tubular casing without the necessity of passing through said cylindrical filter wall of said tubular filter member within the same, carrying any grit or dirt contained in the air admitted through said inlet opening directly into the space surrounding said casing.

4. A primary air admission device for a motor carburetor comprising in combination a tubular casing; an inlet opening at one end of said tubular casing for the fresh air to be admitted to said motor carburetor; a first outlet opening in said tubular casing adapted to be connected to said motor carburetor; a tubular filter member within said tubular casing through which the fresh air is forced to pass on its Way from said inlet opening to said first outlet opening; an unobstructed inlet opening in said tubular filter member connected to said inlet opening at one end of said tubular casing enabling the fresh air to enter said tubular filter member; a second outlet opening in said tubular casing leading into the space surrounding said tubular casing; and an unobstructed outlet opening in said tubular filter member connected to said second outlet opening in said tubular casing through which a portion of the air passing through said tubular casing and said tubular filter within the same might be expelled into the space surrounding said tubular casing without the necessity of passing through the filter wall of said tubular filter member Within the same. carrying any grit or dirt contained in the air admitted through said inlet opening directly into the space surroundin said casing.

5. A primary air admission device for a motor carburetor comprising in combination a tubular casing having a substantially cylindrical wall; an inlet opening at one end of said tubular casing for the fresh air to be admitted to said motorcarburetor; a first outlet opening in said cylindrical wall of said tubular casing adapted to be connected to said motor carburetor; a tubular filter member arranged within said tubular casing and having a, substantially cylindrical filter wall through which the fresh air is forced to pass on its way to said first outlet opening; an unobstructed inlet opening at one end of said tubular filter member connected to said inlet opening at one end of said tubular casing enabling fresh air admitted through said inlet opening at one end of said tubular casing to enter said tubular filter member; a second outlet openin at the other end of said tubular casing leading into the space surrounding said tubular casing; and an unobstructed outlet opening at the other end of said tubular filter member connected with said second outlet opening at the other end of said tubular casing through which a portion of the air passing through said tubular casing and said tubular filter within the same might be expelled into the space surrounding said tubular casing without the necessity of passing 5 6 through said cylindrical filter wall of said tubular filter member within the same, carrying any REFERENCES CITED grit or dirt contained in the air admitted through Th l ow n ref reniws are of record in the said inlet opening directly into the space surfi Of this P rounding said casing. 5 UNITED STATES PATENTS ELLIS SMITH. Number Name Date NORRIS CRABTREE 1,513,036 Donaldson Oct. 28, 1924 SYDNEY NAY'LOR. 1,591,677 Garner July 6, 1926 HAROLD JAMES 10 1,717,369 Clements June 18, 1929 1,922,469 Borthwick Aug. 15, 1933 2,407,194 Vokes Sept. 3, 1946 

